Design and experiment of a four-station laser tracker multilateration measurement system and evaluation of uncertainties

To enhance the pre-alignment accuracy of the Hefei advanced light facility as a fourth-generation low-energy synchrotron radiation device, a four-station laser tracker multilateration measurement system (FLTMMS) has been constructed, which can reduce beam energy loss. To ensure the FLTMMS possesses excellent performance, we have adopted geometric relationships and incident angles to reflective target spheres as the core design principles. By applying these principles, we have established an accurate design model for the FLTMMS to reduce the loss of accuracy caused by a large incident angle to the target ball exceeding its specific angle. At the same time, the uncertainty of the system parameters of the FLTMMS is obtained using the Monte Carlo method, and the calculation of the coordinate measurement uncertainty of the FLTMMS is completed. Then, we verify the uncertainty based on actual measurement data to get the measurement performance of FLTMMS.